Skip to contents

Add custom spectral indexes

Source: R/MODIStsp_addindex.R
MODIStsp_addindex.Rd

Function used to add a user-defined Spectral Index to the default list of computable spectral indexes. Execution without the GUI (i.e., to add a new index from a script) is also possible (see examples).

Usage

MODIStsp_addindex(
  new_indexbandname = "",
  new_indexfullname = "",
  new_indexformula = "",
  new_indexnodata_out = "32767"
)

Arguments

new_indexbandname

character short name (acronym) of the new spectral index (Ignored if gui == TRUE), Default: NULL

new_indexfullname

character extended name (acronym) of the new spectral index (Ignored if gui == TRUE), Default: NULL

new_indexformula

character string containing the formula of the new spectral indexes (Ignored if gui == TRUE). Variables allowed in the formula are the names of the bands: b1_Red, b2_NIR, b3_Blue, b4_Green, b5_SWIR, b6_SWIR and b7_SWIR. Default: NULL

new_indexnodata_out

character nodata value to use for rasters containing the new index

Value

The function is called for its side effects. On success, the MODIStsp_indexes.json is modified so to allow computation of the additional indexes.

Details

  • The function asks the user to provide the info related to the new desired Spectral Index, checks for correctness of provided information (e.g., correct bandnames, computable formula, etc...). If the index is legit, it modifies the MODIStsp_addindex.json file so to allow computation of the additional index within MODIStsp for all products containing the required reflectance bands.

  • To remove all custom-added spectral indexes, run MODIStsp_resetindexes()

Note

License: GPL 3.0

See also

MODIStsp_resetindexes

Author

Lorenzo Busetto, phD (2014-2017)

Luigi Ranghetti, phD (2015)

Examples

# Run the GUI to interactively define a new index
 if (FALSE) {
 MODIStsp_addindex()}

# Define the new index in non-interactive execution

if (FALSE) {
MODIStsp_addindex(new_indexbandname = "SSI",
  new_indexfullname = "Simple Useless Index",
  new_indexformula = "b2_NIR+b1_Red")
}